Media handling systems are used in the computer industry for maintaining large databases which may consist of, for example, many disk or tape cartridges. Various features and components of media handling systems are disclosed in U.S. Pat. Nos. 4,998,232 dated Mar. 5, 1991 for OPTICAL DISK HANDLING APPARATUS WITH FLIP LATCH of Methlie et al.; 5,014,255 dated May 7, 1991 for OPTICAL DISK CARTRIDGE HANDLING APPARATUS WITH PASSIVE CARTRIDGE ENGAGEMENT ASSEMBLY of Wanger et al.; 5,010,536 dated Apr. 23, 1991 for CARTRIDGE HANDLING SYSTEM of Wanger et al.; 5,043,962 dated Aug. 27, 1991 for CARTRIDGE HANDLING SYSTEM of Wanger et al.; 5,101,387 dated Mar. 31, 1992 for LATERAL DISPLACEMENT CONTROL ASSEMBLY FOR AN OPTICAL DISK HANDLING SYSTEM of Wanger et al.; 5,184,336 dated Feb. 2, 1993 for LATERAL DISPLACEMENT CONTROL ASSEMBLY FOR AN OPTICAL DISK HANDLING SYSTEM of Wanger et al.; and copending U.S. patent application Ser. No. 08/020,160 filed Feb. 18, 1993 for LINEAR DISPLACEMENT AND SUPPORT APPARATUS FOR USE IN A CARTRIDGE HANDLING SYSTEM of Luffel et al., which are each hereby specifically incorporated by reference for all that is disclosed therein.
In general, a media handling system may include a storage system for storing disk or tape cartridges at corresponding storage locations. The storage locations may be arranged in a two-dimensional array consisting of a combination of vertically extending columns and horizontally extending rows. A media handling system may also include an engaging assembly for retrieving and transporting cartridges between their storage locations and media (e.g., disk or tape) drives.
To facilitate horizontal and vertical movement of the engaging assembly among the storage locations and media drives, the media handling system may further include one or more apparatuses for linearly (horizontally or vertically) displacing the engaging assembly. A linear displacement apparatus may utilize one or more elongate flexible members such as cables, ropes, belts, or chains (see, for example, copending U.S. patent application Ser. No. 08/020,160 incorporated by reference above). The elongate flexible members may be attached to the engaging assembly and mounted on pulleys, gears or the like which maintain the elongate flexible members in tension. At least one of the elongate flexible members may be engaged with and driven by a drive mechanism which causes linearly displacement of all of the elongate flexible members and the engaging assembly attached thereto. The drive mechanism may consist of a motor and a system of linkages ("gearbox") connecting the motor to one or more of the elongate flexible members.
A conventional gearbox may comprise various combinations of gears to adjust the linear displacement speed of the elongate flexible member in relation to the rotational speed of the motor. For example, to reduce the speed of the elongate flexible member in relation to the motor, a relatively small gear attached to the motor may be engaged with a relatively larger gear, which is coupled with a capstan or the like which engages the elongate flexible member. Such speed reduction may also be performed in several stages. For example, two-stage speed reduction may be accomplished by engaging a first gear, which is coupled with a capstan or the like, with a second, relatively smaller gear. The second gear is coupled with a third gear, which is engaged with a fourth gear. The fourth gear is relatively smaller than the third gear and is coupled to a motor.